This digital library was developed for professionals seeking to design, conduct, document, or review project evaluations. The Online Evaluation Resource Library (OERL) provides a large collection of sound plans, reports, and instruments from past and current project evaluations in several content areas, as well as guidelines for how to improve evaluation practice using the web site's resources. OERL's resources include instruments, plans, and reports (the tabs across the top of this page) from evaluations that have proven to be sound and representative of current evaluation practices. Professional development modules as well as presentations and papers are also included.